A game in which a player character controlled by a player attacks a target object such as an enemy character is known. In order to play this kind of game easily, as described in JP2007-272123 and JP2010-017395, a game in which an lock-on function is provided for fixing a target object to be attacked within the field of view is known.
The lock-on functions described in the prior arts notify that which of the target is a lock-on target by surrounding the target object displayed in the game image, that is, the target object itself which exists in the game space, with a frame showing the lock-on target to the player.
However, in a display method of the prior art, an image of the game space is complicated, and in addition to this, it is only possible to specify an object within the field of view of the virtual camera of the game space, that is, within an area displayed on the display, as the lock-on target.